1. Field of the Invention
The invention relates to an abrasive cleaning device and method for cleaning using a water jet in which abrasive particles are entrained.
2. Description of the Prior Art
For the cleaning or abrading of surfaces it is known to use devices and methods that deliver particles of an abrasive material. These devices have a nozzle through which a gas or liquid stream is directed, which stream has the abrasive particles entrained therein. Devices of this type are also known wherein two streams are mixed with one having particles and the other having a liquid to form the jet of abrasive particles entrained in liquid for cleaning.
With prior-art devices and methods of this type, it has heretofore been impossible to achieve a combination of the high jet velocity required for effective cleaning, a compact structure that may be easily manipulated and used for cleaning closely confined areas such as the interior of pipe or tubing, and resistance to rapid deterioration caused by the high velocity abrasive particles passing through the device during use. In devices of this type where the jet with the entrained abrasive particles passes through the nozzle at high velocity or is mixed within the nozzle with a liquid carrier stream, excessive wear of the nozzle results. In devices wherein the particles are mixed outside the nozzle, the required compactness for easy manipulation and use in cleaning confined areas, such as pipe and tubing, cannot be achieved.